DE102013005001A1 - Broadband monopole antenna for two frequency bands separated by a frequency gap in the decimeter wave range for vehicles - Google Patents

Abstract

The invention relates to a vertical broadband monopole antenna for two frequency bands separated by a frequency gap - the lower band for the lower frequencies and the upper band for the higher frequencies - both located in Dezimeterwellenbereich, for vehicles and for transmission and / or reception with terrestrial emitted vertically polarized radio signals over a substantially horizontal conductive base (6) as a vehicle mass with an antenna connection point (3) located in the monopole base. The broadband monopole antenna (0) is formed of an upper band monopole (1) and a lower band monopole combined and made of a mechanically stiff electrically conductive film (33) as a continuous, electrically conductive planar structure over a conductive base (6) substantially designed to run in a direction perpendicular to this oriented plane. At the lower end of the broadband monopole antenna (0) there is a flat triangular structure (4) on the top as a top band monopole (1) with a substantially horizontally oriented baseline in the top band monopole height (8) above the conductive base (6) whose tip is connected to the antenna connection point (5). Adjacent to the upper end of the monopole antenna (0) located in the antenna height (9) above the conductive base surface (6), a roof capacitance (10) designed essentially as a flat rectangular structure (16) is designed underneath. The flat triangular structure (4) and the flat rectangular structure (16) as a roofing capacitance (10) are inductively connected to high impedance by at least one conductor strip (15) with a narrow stripline width (14) for separating radio signals in the upper band, whereby the subband monopole (2) educated.

Description

The invention relates to a vertical broadband monopole antenna for two frequency bands separated by a frequency gap - the lower band for the lower frequencies and the upper band for the higher frequencies - both located in Dezimeterwellenbereich - for vehicles and for transmission and / or reception with terrestrial emitted vertically polarized radio signals over a substantially horizontal conductive base 6 as vehicle mass with an antenna connection point located in the monopole base 3 consisting of the antenna connection point 5 and the ground connection 7 ,

Broadband antennas having these features are known, for example, from Japanese Unexamined Patent Publication No. JP 10-242740 , These antennas are designed as multi-resonant rod antennas, wherein the coverage of a plurality of frequency bands separated by frequency gaps in frequency by means of multiple, applied to the elongated rod wire windings, which overlap partially. Such antennas are used for transmission and reception in the decimeter-wave range on vehicles, preferably in each case on the vehicle roof. Antennas of this type, on the one hand, have the disadvantage that they are only provided for relatively narrowband frequency bands separated from one another by frequency gaps, and that they are only of limited use for wide frequency bands. Especially for use on vehicles, the height, their aerodynamic shape and their wind resistance value are important. However, the special significance is due to the usual in vehicle large numbers of economic efficiency of the production of such an antenna. This shows that the application of different wire windings must be mechanically very tight tolerances, so that the required frequency accuracy is achieved. Furthermore, the application of the windings on the rod, their attachment and the production of their long-term stability and the reproducibility of the performance of the antenna are relatively complicated and economically expensive.

The large number of modern mobile radio networks, such as those designed or still under development under the LTE (Long Term Evolution) mobile communications standard, require extremely wide bandwidth antennas, for example, the LTE mobile communications standard has a frequency range between 698 and 960 MHz denoted by subband - and provided above a frequency gap of the frequency range between 1460 MHz and 2700 MHz, which is referred to below as the upper band, as in 1 shown. Frequently, an additional middle band in the frequency range between 1460 MHz and 1700 MHz is provided, which is assigned to the upper band. With regard to the antenna function, the frequency gap between lower band and upper band is desired for protection against the radio services located there. For this application antennas are needed, which are suitable in addition to the electrical function for vehicles, with the economy of production is of particular importance.

The object of the invention is therefore to provide an antenna for two separated by a frequency gap frequency bands, which at low height and favorable aerodynamic properties has the necessary mechanical stability and can be produced economically, especially in a simple manufacturing process.

• – Die Breitband-Monopolantenne 0 ist aus einem Oberband-Monopol 1 und einem Unterband-Monopol kombiniert gebildet und ist aus einer mechanisch steifen elektrisch leitenden Folie 33 als zusammenhängende, elektrisch leitende flächige Struktur über einer leitenden Grundfläche 6 im Wesentlichen in einer senkrecht zu dieser orientierten Ebene verlaufend gestaltet.
• – Am unteren Ende der Breitband-Monopolantenne 0 ist eine auf der Spitze stehende flächige Dreieckstruktur 4 als Oberband-Monopol 1 mit im Wesentlichen horizontal orientierter Grundlinie in der Oberband-Mnopolhöhe 8 über der leitenden Grundfläche 6 vorhanden, deren Spitze mit dem Antennenanschlusspunkt 5 verbunden ist.
• – Angrenzend an das in der Antennenhöhe 9 über der leitenden Grundfläche 6 befindliche obere Ende der Breitband-Monopolantenne 0 ist darunter eine im Wesentlichen als flächige Rechteckstruktur 16 ausgeführte Dachkapazität 10 gestaltet.
• – Die flächige Dreieckstruktur 4 und die flächige Rechteckstruktur 16 als Dachkapazität 10 sind durch mindestens einen Leiterstreifen 15 mit schmaler Streifenleiterbreite 14 zur Abtrennung von Funksignalen im Oberband induktiv hochohmig verbunden, wodurch der Unterband-Monopol 2 gebildet ist.

According to the invention, the antenna comprises a vertical wideband monopole antenna for two frequency bands separated by a frequency gap - the lower band for the lower frequencies and the upper band for the higher frequencies - both located in the decimeter wave range, for vehicles and for transmission and / or reception with terrestrial radiated vertically polarized radio signals over a substantially horizontal conductive base 6 as vehicle mass with an antenna connection point located in the monopole base 3 consisting of the antenna connection point 5 and the ground connection point 7 and has the following features

• - The broadband monopole antenna 0 is from a top band monopoly 1 and a subband monopole formed in combination and is made of a mechanically stiff electrically conductive film 33 as a contiguous, electrically conductive planar structure over a conductive base 6 designed substantially in a plane perpendicular to this oriented plane.
• - At the bottom of the broadband monopole antenna 0 is a flat triangular structure standing on top 4 as a top band monopoly 1 with a substantially horizontally oriented baseline in the top band mnopole 8th above the conductive base 6 present, the top of which with the antenna connection point 5 connected is.
• - Adjacent to the in the antenna height 9 above the conductive base 6 located upper end of the broadband monopole antenna 0 is one of them essentially as a flat rectangular structure 16 executed roof capacity 10 designed.
• - The flat triangular structure 4 and the flat rectangular structure 16 as roof capacity 10 are through at least one conductor strip 15 with narrow stripline width 14 for the separation of radio signals in the upper band inductively connected high impedance, causing the sub-band monopole 2 is formed.

The invention will be explained in more detail below with reference to exemplary embodiments. The accompanying figures show in detail:

1 : Frequency ranges according to the LTE mobile standard as an example for two frequency bands separated by a frequency gap in the decimeter wave range with a frequency range between 698 and 960 MHz as a subband and a frequency range between 1460 MHz and 2700 MHz as the upper band above a frequency gap

2 : Two-dimensional broadband monopole antenna 0 according to the invention over the electrically conductive base 6 and the antenna junction formed at the base 3 with a flat triangular structure on top 4 as a top band monopoly 1 and the roof capacity 10 which has two conductor strips 15 with meandering form 24 with the triangle structure 4 for the formation of the subband monopoly 2 are connected. The structure of the broadband monopole antenna 0 can be holistically punched or cut from sheet metal.

3 : Broadband monopole antenna 0 according to the invention as in 2 , combined with a concentric to the top of the flat triangular structure 4 concentrically shaped annular satellite receiving antenna 25 , To further increase the inductive effect of the conductor strips 15 are exemplary further meandering forms 24 educated.

4 : Example of a conductive foil or sheet produced by punching or cutting structure with the frequency response of an electrical parallel resonant circuit 29 in the conductor strip 15 to design the frequency-selective separation of the subband monopole 2 from the upper band monopoly 1 , The parallel resonant circuit 29 is by interdigital structure 26 as parallel capacity 27 and the conductor loop as a parallel inductance 28 educated.

5 : Two-dimensional broadband monopole antenna 0 like in the 2 and 3 , wherein the flat triangular structure 4 of the upper band monopoly 1 by in the triangular plane fan-like arranged and at the lower triangle peak running together strip-shaped slats 20 is designed. The lamellae which are connected to one another exclusively via the triangle tip 20 cause the electromagnetic decoupling of the upper band monopole 1 from the annular satellite receiving antenna 25 ,

• a) Schwankung des Antennengewinns über dem Azimutwinkel Phi der Satellitenempfangsantenne 25 in dBi bei Vorhandensein der flächigen Dreiecksstruktur 4 als geschlossene elektrisch leitende Fläche
• b) wie in a) jedoch mit durch fächerartig verlaufende, streifenförmige Lamellen 20 gestaltete Dreieckstruktur 4.

6 :

• a) Variation of the antenna gain over the azimuth angle Phi of the satellite receiving antenna 25 in dBi in the presence of the flat triangular structure 4 as a closed electrically conductive surface
• b) as in a ) but with fan-shaped, strip-shaped lamellae 20 designed triangle structure 4 ,

The azimuthal variations are shown for the zenith angles theta (angles to the vertical, i.e. z-axis) 20 °, 45 ° and 60 °, respectively.

7 : Monopole antenna as in 4 with annular satellite receiving antenna 25 however, to improve the electromagnetic decoupling between this and the subband monopole 2 the roof capacity 10 forming flat rectangular structure 16 by vertically separated from each other, but at its upper end over a remaining strip 31 continuous strip-shaped roof lamellae 19 is formed.

8th : Monopole antenna as in 7 , but with only one conductor strip 15 with greater sheet thickness in favor of special mechanical rigidity and to achieve the necessary own inductance of the conductor strip 15 with correspond several meandering forms 24 ,

9 : Monopole antenna as in 7 , but with a instead of the flat triangular structure conical and standing on the top formed upper band monopole 1 to increase the bandwidth in the upper band. The electrically conductive conical surface is indicated by dots.

10 : Upper-band monopoly 1 like in the 5 . 7 and 8th However, wherein the fan-like in the lower triangle tip finned strip-shaped fins 20 of the upper band monopoly 1 in the way out of the plane of the flat triangular structure 4 are that they are roughly like the generatrices of a 8th on the top of standing cone with circular or elliptical cross section.

11 : Top view of an antenna according to the invention according to the in 10 indicated section line AA 'to clarify the course of the fan-like strip-shaped slats 20 , The annular satellite receiving antenna 25a and 25b are indicated by broken lines.

12 : Maximum value of the azimuthal in fluctuation of the antenna gain in dBi with closed electrically conductive cone sheath and with a strip-shaped lamellae 20 formed Cone sheath depending on the zenith angle (angle against the z-axis).

13 : Installation situation of a broadband monopole antenna under a cover 32 looking at the antenna transverse to the direction of travel (y-direction) together with an annular satellite receiving antenna 25 the black led and marked with a) ladder parts, these are the conductor strips 15a , the roof louvers 19a as well as the strip-shaped lamellae 20a are from the yz plane of the flat triangular structure 4 in the direction of the x-axis and accordingly the conductor strips 15b , the roof louvers 19b as well as the strip-shaped lamellae 20b are in the direction of the negative x-axis, so that a spatial antenna structure is formed.

14 : Installation situation according to 13 but with a view to the arrangement in the direction of travel.

15 : Installation situation of two broadband monopole antennas 0 and 0a according to 14 in the direction of travel behind each other under a common cover 32 consisting of upper band monopoly 1 respectively. 1a and lower band monopoly 2 respectively. 2a each with an annular satellite receiving antenna 25a respectively. 25b at the foot of the broadband monopole antenna 0 respectively. 0a ,

16 : Broadband monopole antenna 0 according to the invention as in 2 , wherein the electrically conductive foil 33 given by the metallic coating of a printed circuit board and the printed circuit board with its coating approximately in accordance with the contours of the broadband monopole antenna 0 represented by the cut lines of the dielectric plate 34 , is designed.

A particular advantage of a broadband monopole antenna 0 According to the invention, the property is that at the antenna connection point 3 measurable impedance broadband in the vicinity of the prescribed for antenna systems for vehicles standard impedance of Z0 = 50 ohms can be made largely problem-free. This also results in the economic advantage that a matching network between the antenna connection point 3 at the bottom of the broadband monopole antenna and the continuing circuit usually omitted or at least can be designed particularly low effort. The following is an example of a broadband monopole antenna 0 according to the invention for the two separated by a frequency gap frequency ranges according to the in 2 illustrated lower band and the upper band explained. The broadband monopole antenna in its flat designed basic version in 2 is essentially a subband monopoly 2 to cover the lower band with a required antenna height 9 in combination with a top band monopoly 1 with the upper band monopoly height 8th with a common antenna connection point 3 educated. To avoid excessive effective antenna height 9 in the frequency domain of the upper band is the lower band monopole 2 from in the frequency range of the upper band inductively high impedance conductor strips 15 with narrow stripline width 14 in conjunction with a roof capacity 10 designed. The latter is essentially a flat rectangular structure 14 executed with compared to the vertical extent 22 large horizontal extent 23 designed.

To meet the demand for the simplest and most economical method of production, the monopole antenna according to the invention is made of an electrically conductive film 33 as a continuous, electrically conductive planar structure substantially perpendicular to the conductive base 6 extended level extended. Here it turns out to be a particularly advantageous embodiment of the invention, metallically conductive sheet as a conductive film 33 to use, resulting in the entire broadband monopole antenna 0 can produce a mechanically self-supporting structure. This structure can be produced, for example, by a standing process or by a controlled cutting process, for example by controlled laser cutting. In this case, the production of a punching tool will prove to be economically advantageous in particularly large numbers, because the monopole antenna can be multiplied by automated punching operations extremely cost. On the other hand, with smaller quantities the computer-controlled laser cutting can be more economical. The production of the broadband monopole antenna 0 sheet metal offers the particular advantage of metallic rigidity, which is of particular importance for use as a vehicle antenna. A particular advantage of this flat structure is their negligible wind resistance, if it is designed to extend in an advantageous manner in a plane whose normal is oriented perpendicular to the direction of travel of the vehicle. Furthermore, the electrically conductive film 33 be selected in an advantageous embodiment of the invention by the metallic coating of a dielectric plate, that is a printed circuit board. It should be noted, however, that a coming into consideration for economic reasons material for the circuit board in the decimeter wave range is lossy, so that is provided according to the invention, the structure of the broadband monopole antenna 0 to print on the circuit board in a known per se, but this according to the outlines of the broadband monopole antenna 0 with a slight projection to keep the course of electric field lines in the lossy dielectric plate as small as possible. The trimming of the dielectric plate along the dashed line dotted cutting lines 34 is in 16 shown. This form of representation is particularly in complicated geometric structure of the broadband monopole antenna 0 advantageous because the cutting lines 34 less finely designed following the geometric structure and therefore require a less expensive punching tool.

For a broadband monopole antenna 0 This type is required, for example, for the adaptation of antenna systems to the standard impedance of Z0 = 50 ohms prescribed for vehicles in the above-described subband VSWR (voltage standing wave ratio) <3. This value may be in an antenna according to the invention in its full implementation at the antenna connection point 3 already with an antenna height 9 of 6 cm can be achieved in principle. The properties of the subband monopoly 2 are essentially determined by its antenna height 9 and by the size of the flat roof capacity 10 whose horizontal extent 23 With about 6 cm much larger, that is designed at least three times larger than the vertical extent 22 , A much larger vertical extent 22 increases the capacity value of the roof capacity 10 but reduces the effective level of the subband monopole 2 which, in contrast to the capacitance value, is square in the formation of the frequency bandwidth of the subband monopole 2 received.

The formation of the upper band monopoly 1 is essentially due to the flat triangular structure 4 given, provided the inductive effect of the conductor strips 15 with narrow stripline width 14 for the separation of radio signals in the upper band from the roof capacity 10 is sufficiently large. To increase this separating effect is provided according to the invention, the conductor strips 15 with meandering characteristics 24 to provide. Naturally, the functional subdivision of the broadband monopole antenna is 0 in the subband monopoly 2 and the upper band monopoly 1 not strict to see. Rather, the transition between the effects is fluent and the subdivision is to be understood as a description of the main effects in the two frequency ranges. The mode of action of over the conductive base 6 located upper band monopoly 1 is essentially due to the design of the flat triangular structure 4 given. In the interest of a particularly broadband behavior, according to the invention, there is a flat triangular structure standing on top 4 with triangle opening angle 12 provided, the top of which with the antenna connection point 5 connected is. Through this is together with the ground connection point 7 on the conductive base 6 the antenna connection point 3 for the broadband monopole antenna 0 educated. The height of the baseline of the flat triangular structure 4 above the conductive base 6 essentially forms the effective upper band monopole height 8th , by which the frequency behavior of the upper band monopoly 1 is essentially determined. For reasons of the vertical radiation pattern for communication with terrestrial transmitting and receiving stations, the upper band monopole should be used 8th at the upper frequency limit of the upper band should not be greater than about 1/3 of the free space wavelength at that frequency. As a triangle opening angle 12 Values between 30 and 90 degrees have proved favorable. The resulting broad band-effect triangle structure makes it possible, for example, to comply with the frequently asked requirement for impedance matching at the base point, the value of VSWR <2.5 in the frequency range of the upper band.

According to the task with regard to the required mechanical stability for holding the roof capacity 10 through narrow conductor strips 15 It is inventively provided to perform this mechanically sufficiently stiff. In a particularly advantageous embodiment of a punched or cut sheet as a conductive film 33 executed broadband monopole antenna 0 according to the invention is a frame structure 11 designed to achieve a special rigidity. Here is the frame structure 11 as in the 2 and 3 shown, from two at a sufficient distance 13 each other guided narrow conductor strip 15 , the baseline of the flat triangular structure 4 and the flat rectangular structure 16 the roof capacity 10 educated.

In a further advantageous embodiment of the invention, the electrically conductive foil 33 made of a material of special rigidity. When using such materials, the broadband monopole antenna can 0 with only one conductor strip 15 , as in 8th represented, designed. In the interest of mechanical stability for this, however, then a larger stripline width 14 provided. To design a sufficiently large inductive effect of the conductor strip 15 usually turn out to be several meandering forms 24 as necessary.

To fine tune the interaction between the subband monopole 2 and the upper band monopoly 1 it is provided in an advantageous embodiment of the invention, a switching element with the operation of a parallel resonant circuit 28 in the conductor strips 15 contribute. This parallel resonant circuit serves to support the frequency selective separation of the subband monopole 2 of signals in the upper band. According to the invention, the parallel resonant circuit 28 , as in 4 each represented as an interdigital structure 26 executed parallel capacity 27 and a parallel conductor designed as a strip conductor 28 , Also, this switching element can be punched example of sheet metal or cut over the conductor strips 15 in the design of the mechanically self-supporting broadband monopole antenna 0 be included.

To further improve the frequency bandwidth of the upper band monopole 1 In an advantageous embodiment of the invention for this a three-dimensional structure, which is formed from the two-dimensional structure in such a way that instead of the flat triangular structure 4 an approximately conical structure is desired. The form of such a monopoly is in 9 based on the cone-shaped monopoly 18 indicated with electrically conductive lateral surfaces. In this case, the economically advantageous manufacturability of punched or cut sheet should be maintained. According to the invention, it is therefore provided, the flat triangular structure 4 by in the lower triangle tip fan-like together running strip-shaped lamellae 20 , as in 5 shown to execute. By wagging the slats 20 in the form of the generatrix lines of a cone standing on top to cone lamellae 30 becomes the cone-shaped monopoly 18 in 9 in view of its effect as a top-band monopoly 1 simulated. This is in 10 shown in detail and also according to the section AA 'in 11 seen as a plan view. In 11 is the in 10 indicated cone cross section elliptical and thus the cone opening angle 17a In the x-direction due to the requirements with respect to the aerodynamic properties of the antenna chosen smaller than the cone opening angle 17 in the direction of travel of the vehicle (y-direction).

Due to the limited space available in vehicle antennas is the essential requirement for smallness and in particular to minimize the floor plan of the antenna. In particular for satellite radio services and antennas for other radio services in a confined space, the deformation of the directional diagram of the satellite antenna due to the radiation coupling between the antennas is problematic. This problem exists even if - as in the 3 . 5 . 7 . 8th . 10 . 11 and 15 - at least one concentric with the antenna connection point 3 a broadband monopole antenna 0 arranged annular satellite receiving antenna 25 . 25a is available. For this exists z. B. according to the standard of satellite broadcasting SDARS in the zenith angle range (angle to the z-axis) z. B. between 0 and 60 degrees, the strict requirement for an antenna gain, which depending on the operator for circular polarization of constant z. B. 2 dBi or z. B. 3 dBi at an azimuthal fluctuation of less than 0.5 dB. In 3 is a concentric to the antenna connection point 3 a broadband monopole antenna 0 arranged annular satellite receiving antenna 25 available. In training the upper band monopoly 1 as a closed area arise in the 6a garbled azimuthal variations in the antenna gain of the satellite receiving antenna 25 at about 2.3 GHz. At a zenith angle of 45 degrees, the gain variation of 0.6 dBi is already above the tolerance value and can not be tolerated at 60 degrees with 1.2 dBi. In this context, the design of the flat triangular structure 4 from at the top of fan-like running lamellae 20 , as in 5 , more favorable than a closed flat triangular structure 4 according to 3 , This advantage of little effect on the radiation characteristics of the satellite receiving antenna 25 is in the design of the upper band monopoly 1 made of cone blades 30 particularly pronounced. This is an example of the in 6b under different zenith angles shown azimuthal fluctuations of the antenna gain, which even at a zenith angle of 60 degrees has an experimentally barely detectable variation of 0.07 dB. The difference between the influences of the upper band monopoly 1 in the form of an electrically conductive cone sheath and a sheath of cone lamellae 30 on the azimuthal fluctuation of the antenna gain of the satellite receiving antenna 25 depending on the zenith angle continues to look impressive 12 out. By avoiding ring currents, which from the currents on the satellite antenna 25 On a conductive cone sheath caused by radiation coupling of the two antennas, is in the design of the cone shroud of cone-blades 30 the top band monopoly 1 this without influence on the radiation properties of the satellite receiving antenna 25 ,

Also to the electromagnetic decoupling between the satellite receiving antenna 2 and the roof capacity 10 forming flat rectangular structure 16 of the subband monopoly 2 To perfect, it is according to the invention substantially vertically separated from each other by electrically conductive, but at its upper end over a remaining strip 31 continuous strip-shaped roof lamellae 19 as in the 7 . 8th and 9 shown executed. Their strip width should be 21 not greater than 1/8 of the free space wavelength of the highest frequency in the upper band.

It is often intended to use a broadband monopole antenna 0 under a cover 32 to accommodate plastic as it is in 13 with view on transverse to the direction of travel (-x direction) and in 14 with view on direction of travel (y-direction) is shown. Hereby, the in 14 visible extension of the cover 32 transverse to the direction of travel, the possibility of further spatial design of the originally arealwide produced broadband monopole antenna 0 with the advantages of increasing the bandwidths of both monopolies 1 and 2 , This expresses itself through a better one Configurability of the antenna impedance with respect to the VSWR value at the antenna connection point 3 out. This gives the possibility to be able to largely do without a matching network.

To design the spatiality of the sub-band monopoly 2 According to the invention, at its upper end over a remaining strip contiguous strip-shaped roof blades 19 the roof capacity 10 in the way that they are arranged in the projection on a plane transverse to the direction of travel V-shaped. These are alternately the in 13 filled in black marked roof slats 19a in the x-direction and the white-filled roof slats 19b deflected in negative x-direction, so that in the projection in 13 visible V-shaped structure is given. Due to the lateral deflection transversely to the direction of travel, the capacity value of the roof capacity 10 greater. This leads to an increase in the bandwidth of the subband monopole 2 and facilitates compliance with the impedance matching condition at the VSWR value to be maintained.

In analogy to the design of a cone with elliptical cross-section by appropriate deflection of the slats 20 . 20a . 20b of the upper band monopoly 1 in 11 can in a further advantageous embodiment of the invention, the slats 20 . 20a . 20b about the inner boundary of the cover 32 following are elicited. That is, the strip-shaped fins running together in the lower triangle tip 20 . 20a . 20b of the upper band monopoly 1 become out of the plane of the flat triangular structure 4 successively bent in the way so that they are arranged in the projection on a plane transverse to the direction of travel approximately V-shaped. Same as above for the roof slats 19 . 19a . 19b described, are the fins 20 in the way that the in 13 filled in black 20a in the x-direction and the white filled filled slats 20b deflected in negative x-direction, so that in the projection in 14 visible V-shaped structure is given. Again, this measure serves to increase the frequency bandwidth of the upper band monopole 1 with the associated advantage in realizing the impedance matching in the antenna base. In the realization of antennas, as in the 13 . 14 and 15 are shown, it has proved to be advantageous, and the at least two conductor strips 15 . 15a . 15b spatially execute in such a way that they z. B. by gating at half antenna height 9 by about 45 °, or -45 ° with respect to the y-axis, the available horizontal expansion transverse to the direction of travel within the cover 32 fill out.

In general, it can be observed that the spatial design according to the invention, starting from the described two-dimensional design of the monopole antenna according to the invention 0 regarding the problem of impedance matching over large frequency ranges is also advantageous. The present invention thus has the particular advantage that this spatially designed antenna can be punched or cut from a sheet-like electrically conductive foil and designed by simply subsequently bending, as described above.

Frequently required is two broadband monopole antennas 0 and 0a according to the invention under a cover 32 in the direction of travel one behind the other, as in 15 to install. This shows in practice advantageously that the annular satellite antennas 25 at the base of a broadband monopole antenna 0 by the presence of other broadband monopole antennas 0a no disturbing influence on their radiation properties undergoes. Conversely, this also applies to the effect of the broadband monopole antenna 0 on the satellite antennas 25a at the base of a broadband monopole antenna 0a ,

In a further advantageous application of a broadband monopole antenna 0 According to the invention, this is supplemented by a further, same to this same broadband monopole antenna in a known per se to a dipole. This is the mirror image of the broadband monopole antenna 0 at the conductive base 6 under their omission by this further broadband monopole antenna in such a way replaced, that one to the level of the conductive base area 6 symmetrical dipole is given. The symmetrical antenna connection point of this dipole is between the antenna connection point 5 the broadband monopole antenna 0 and the - the corresponding - at the conductive base 6 mirrored antenna connection point 5 educated.

LIST OF REFERENCE NUMBERS

0, 0a

Broadband monopole antenna

1, 1a

High band monopoly

2, 2a

The sub-band monopoly

3

Antenna connection point

4

flat triangular structure

5

Antenna connection point

6

Leading base area

7

Ground connection point

8th

High band monopole height

9

antenna height

10

top load

11

frame structure

12

Triangle opening angle

13

distance

14

Stripline width

15, 15a, 15b

conductor strips

16

Flat rectangular structure

17

Cone opening angle in the y direction

17a

Cone opening angle in x-direction

18

conical monopole

19, 19a, 19b

roof slat

20

strip-shaped lamellas

21

strip width

22

vertical expansion

23

Horizontal expansion

24

meandering form

25, 25a, 25b

annular satellite receiving antenna

26

Interdigital structure

27

parallel capacitance

28

parallel inductance

29

Parallel resonant circuit

30, 30a, 30b

Cone-plate

31

Remaining strip

32

cover

33

electrically conductive foil

34

Cut lines of the dielectric plate

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• JP 10-242740 [0002]

Claims (16)

Vertical broadband monopole antenna for two frequency bands separated frequency bands - the lower band for the lower frequencies and the upper band for the higher frequencies - both located in the Dezimeterwellenbereich, for vehicles and for transmitting and / or receiving terrestrially emitted vertically polarized radio signals over a substantially horizontal conductive base ( 6 ) as a vehicle mass with an antenna connection point located in the monopole base ( 3 ) with the following features - The broadband monopole antenna ( 0 ) is from a high-band monopoly ( 1 ) and a sub-band monopole formed and is made of a mechanically stiff electrically conductive film ( 33 ) as a contiguous, electrically conductive planar structure over a conductive base area ( 6 ) substantially in a direction perpendicular to this oriented plane running - At the lower end of the broadband monopole antenna ( 0 ) is a flat triangular structure ( 4 ) as a top-band monopoly ( 1 ) with a substantially horizontally oriented baseline in the upper band monopole ( 8th ) above the conductive base ( 6 ) whose tip is connected to the antenna connection point ( 5 ) - adjacent to the antenna height ( 9 ) above the conductive base ( 6 ) located upper end of the monopole antenna ( 0 ) is an essentially as a flat rectangular structure ( 16 ) roof capacity ( 10 ) - The flat triangular structure ( 4 ) and the flat rectangular structure ( 16 ) as roof capacity ( 10 ) are characterized by at least one conductor strip ( 15 ) with narrow stripline width ( 14 ) for the separation of radio signals in the upper band inductively high impedance connected, whereby the sub-band monopoly ( 2 ) is formed. Broadband monopole antenna ( 0 ) according to claim 1, characterized in that the electrically conductive foil ( 33 ) consists of metallic sheet metal and at least two at a sufficient distance ( 13 ) guided narrow strip conductors ( 15 ) are present in such a way that a frame structure ( 11 ), consisting of the baseline of the triangular structure ( 4 ), the flat rectangular structure ( 16 ) and two narrow from mechanically sufficiently rigid conductor strips ( 15 ) is designed, by which a mechanically stable mounting of the roof capacity ( 10 ) given is. 2 . 3 Broadband monopole antenna ( 0 ) according to claim 1, characterized in that the conductor strips ( 15 ) approximately uniformly and for the design of a frequency-selective separation of the subband monopole ( 2 ) of signals in the upper band of sufficient large inductance with narrow stripline width ( 14 ) are designed and, if appropriate, for further inductance increase meandering forms ( 24 ) contain. 2 . 3 Broadband monopole antenna ( 0 ) according to one of claims 1 to 2, characterized in that for the frequency-selective separation of the sub-band monopole ( 2 ) of signals in the upper band in the conductor strips ( 15 ) each have a parallel resonant circuit ( 29 ), consisting of an interdigital structure ( 26 ) parallel capacity ( 27 ) and a parallel conductor designed as a strip conductor ( 28 ) is turned on. 4 Broadband monopole antenna ( 0 ) according to one of claims 1 to 3, characterized in that the triangle opening angle ( 12 ) approximately between 30 and 90 degrees and which is selected and which the upper band monopoly height ( 8th ) forming height of the triangle at the upper frequency limit of the upper band is not greater than 1/3 of the free space wavelength at this frequency. 2 . 3 . 4 Broadband monopole antenna ( 0 ) according to one of claims 1 to 4, characterized in that above the conductive base ( 6 ) at least one concentric with the antenna connection point ( 3 ) arranged annular satellite receiving antenna ( 25 ) and for their electromagnetic decoupling from the upper band monopole ( 1 ) the flat triangular structure ( 4 ) arranged in a fan-like manner in the triangular plane and running together in the lower triangular tip strip-shaped fins ( 20 ) is designed. 5 . 7 . 10 Broadband monopole antenna ( 0 ) according to one of claims 1 to 5, characterized in that in order to improve the electromagnetic decoupling between the latter and the sub-band monopole ( 2 ) the roof capacity ( 10 ) forming flat rectangular structure ( 16 ) substantially separated by vertically electrically conductive, but at its upper end over a remaining strip ( 31 ) contiguous strip-shaped roof lamellae ( 19 ) is formed. 7 Broadband monopole antenna ( 0 ) according to one of Claims 5 to 6, characterized in that the strip-shaped lamellae running together in the lower triangular point ( 20 ) of the upper band monopoly ( 1 ) in the manner of the plane of the triangular structure ( 4 ) are extended so that they extend approximately like generatrices of a cone standing on the top with a circular or elliptical cross-section. 10 Broadband monopole antenna ( 0 ) according to one of claims 5 to 7, characterized in that the monopole antenna ( 0 ) is mounted on the vehicle in such a way that the horizontal extent of the surface roof capacity ( 10 ) runs in the direction of travel. 13 Broadband monopole antenna ( 0 ) according to one of Claims 5 to 6, characterized in that the strip-shaped roof lamellae (8) which are connected at their upper end over a remaining strip ( 19 ) of the roof capacity ( 10 ) of the subband monopoly ( 2 ) are sequentially selected in such a way that they are arranged in the projection on a plane transverse to the direction of travel V-shaped. 14 Broadband monopole antenna ( 0 ) according to one of Claims 5 to 6, characterized in that the strip-shaped lamellae running together in the lower triangular point ( 20 ) of the upper band monopoly ( 1 ) from the plane of the flat triangular structure ( 4 ) are sequentially selected in such a way that they are arranged in the projection on a plane transverse to the direction of travel V-shaped. 14 Broadband monopole antenna ( 0 ) according to one of claims 1 to 10, characterized in that the broadband monopole antenna ( 0 ) under a cover ( 32 ) and the at least two conductor strips ( 15 . 15a . 15b ) are spatially guided in such a way that they are available for them horizontal extent transverse to the direction of travel within the cover ( 32 ) fill out. 14 Broadband monopole antenna ( 0 ) according to one of claims 1 to 6, characterized in that, together with another broadband monopole antenna ( 0 ) according to one of claims 1 to 11 under a cover ( 32 ) is mounted one behind the other in the direction of travel and at least one of the broadband monopole antennas ( 0 ) at least one concentric with the antenna connection point ( 3 ) arranged annular satellite receiving antenna ( 25 . 25a ) is available. 15 Broadband monopole antenna ( 0 ) according to one of claims 1 to 11, characterized in that the electrically conductive film ( 33 ) consists of metallic sheet metal and only a mechanically particularly stiff conductor strip ( 15 ) is present, which to achieve the necessary inductance several meandering forms ( 24 ) contains. 8th Broadband monopole antenna ( 0 ) according to claim 1, characterized in that the electrically conductive foil ( 33 ) is given by the metallic coating on a dielectric plate (printed circuit board) and the dielectrically conductive coating of the printed circuit board according to the planar structure of the monopole antenna ( 0 ) is designed and the printed circuit board according to the cut lines of the dielectric plate ( 34 ), which are approximately along the contours of the planar structure of the broadband monopole antenna ( 0 ), is cut out. 16 Broadband monopole antenna ( 0 ) according to claim 1 to 15, characterized in that the mirror image of the broadband monopole antenna ( 0 ) at the conductive base ( 6 ) is replaced by its omission by a same to this other broadband monopole antenna in such a way that one to the level of the conductive base ( 6 symmetric dipole and the symmetrical antenna connection point of this dipole between the antenna connection point ( 5 ) of the broadband monopole antenna ( 0 ) and - according to this - at the conductive base ( 6 ) mirrored antenna connection point ( 5 ) is formed.

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